Can You Run a Swamp Cooler When the Air Conditioner Is on?

Warning

A swamp cooler works best in hot areas with low humidity because a swamp cooler adds humidity to the air. On the other hand, an air conditioner removes humidity from the air, which is why you shouldn't use a swamp cooler and an air conditioner at the same time. If you use them together, neither one will provide sufficient cooling.

The Arizona desert was the catalyst behind the swamp cooler. The Consumer Energy Center reports that, during the 1920s, Arizona residents would hang water-soaked linen inside of screened-in sleeping porches. The residents would use electric fans to draw hot air through the wet linen, and the room would get cooler. That idea eventually resulted in the swamp cooler. Basically, a swamp cooler is a cooling system that contains moist pads and a fan. Water in the unit moistens the pads, and fresh air from outside is sucked through the water-saturated pads, cooled by the process of evaporation and then circulated throughout the house by a blower. If the air has too much humidity, the swamp cooler cannot work effectively. It needs a steady supply of dry, arid air.

The U.S. Department of Energy reports that a swamp cooler is less expensive than a central air unit. Not only does a swamp cooler cost less to install, but it also uses less energy than a central air unit. Another benefit is that the pads in some models filter pollen and other allergens out of the air. As for installation, you can install a swamp cooler on a roof, in an attic or in a window.

You can do several things to get the best performance and most use out of a swamp cooler. Water Wise recommends turning the unit on only after the outside temperature reaches 85 degrees F or greater. Performing this simple step leads to a 50 percent savings in your water use. The unit contains a water pump that moistens the pads. If you turn the water pump on before the fan, the pads will become saturated ahead of time and make the cooler perform better. Opening windows slightly and using ceiling fans also can make your swamp cooler more efficient.